Don't know whether anyone has done this, but it seems like an obvious fix for a leaky drain tube: I cut the center joint out, using a hacksaw blade (small plastic handle, accepts std. hacksaw blade but allows the blade to stick out unsupported in front -- great for tight spaces) and replaced it with a length of silicone hose -- 3/4" I.D. fits perfectly.

No more leaks at the junction, and it will be far easier to disassemble the whole works in the future, if need be.

I got frustrated after taking it all apart, replacing the o-rings etc., and it still leaked! Wasn't about to pull the turbo again.

I am not too worried about the hose deteriorating, as many people adding turbochargers to engines that didn't originally have them use silicone hose for oil lines with good results. If it does, it's 20 minutes to toss another one on.